How soldiers deal with the job of killing

[JMA]

Which country was ever well-prepared for major war since the 1880's?

I can identify examples for the early and mid 19th century, but none later.
Maybe my expectations are just really high, but judging by your question yours aren't exactly low either.

Took me immediately to the words of your Von Schell circa 1930.

Quite rightly he noted that the US homeland had no real threat of sudden invasion from anyone. They could therefore take their time to prepare for any war (WW1 and WW2) and enter it at a time and place of their choosing when ready. They then have time to start up those massive (and effective) Henry Ford style industrial and manpower production lines in their build up to a major war.

As such US forces can remain dispersed in their various 'camps and forts' to cater for any future sudden uprising of the indigenous Indian population.